Probiotics Not the Answer to Reduce C. Difficile Risk

Emily Heil, MD

New research does not support the use of probiotics strictly to reduce the incidence of Clostridium difficile infections (CDI).

A team, led by Emily L. Heil, PharmD, MS, University of Maryland School of Pharmacy, Department of Pharmacy Practice and Science, evaluated the impact of a computerized clinical decision support tool (CCDS) that helps clinicians prescribe probiotics primarily prevention of CDI in adult hospitalized patients.

A main goal of hospitals across the world is to prevent C difficile infections from spreading and it has long been a theory that probiotics could be a useful tool in interfering with colonization and infections.

The Support tool

In the study, the CCDS tool was implemented into the electronic medical records at 4 hospitals promoting prescription of a probiotic preparation at the time of antibiotic prescription in high-risk patients in May 2019.

The researchers conducted interrupted time series using segmented regression analysis to evaluate hospital-wide CDI incidence for the year before and after CCDS implementation.

The team also used multivariable logistic regression to evaluate C difficile incidence in patients qualifying for probiotics in the pre-intervention period compared to the post-intervention period, adjusting for potential confounders.

Finally, they developed propensity score matched pairs to evaluate CDI risk by receipt of probiotics, while adjusting for potential differences in patients who received probiotics in the post-intervention period.

The Impact of Probiotics

The quarterly C difficile incidence increased over time in the post-intervention period compared to baseline trends (slope change, 1.4; 95% CI, 0.9-1.9), with an odds ratio (OR) of 1.41 in eligible patients post-intervention compared to pre-intervention (aOR, 1.41; 95% CI, 1.11-1.79).

In the propensity score matched analysis, the investigators found patients who received probiotics did not have lower rates of CDI compared to patients who did not receive probiotics. (OR, 1.46; 95% CI, 0.87-2.45).

“Use of probiotics for primary prevention of CDI among adult inpatients receiving antibiotics is not supported,” the authors wrote.

C Difficile and COVID-19

While evidence does not support the use of probiotics, some of the measures put in place because of COVID-19 has resulted in a decrease in CDI rates.

Gastrointestinal symptoms has been a hallmark of COVID-19 since the beginning of the pandemic, with about a third of patients suffering from diarrhea.

While the US Food and Drug Administration (FDA) has yet to approve a treatment for COVID-19, hospitalized patients often are treated with broad-spectrum antibiotics, which is escalated as the clinical status of the patients deteriorates.

However, this class of treatment has been associated with an increased risk of CDI, even as hospitals take measures to limit the person-to-person spread of the virus.

The researchers compared outcomes and mortality for hospitalized COVID-19 patients with and without CDI. All CDI patients were exposed to at least 2 (2-8) antibiotics prior to their CDI diagnosis.

Overall, there were 97 (24.9%) patients who were tested for CDI, with a mean age of 62.4 years old. Of this group, 5 (5.2%) patients tested positive for CDI, which was lower than the overall inpatient CDI-positive rate in 2019 (n = 280; 9.8% of tests performed). However, this was not statistically significant (P = 0.16).

The study, “A Multi-Center Evaluation of Probiotic Use for the Primary Prevention of Clostridioides difficile infection,” was published online in Clinical Infectious Diseases.